"If you were to see my calendar, you'd probably notice a host of time slots greyed out but with no indication of what's going on. There is no problem with my Outlook or printer. The grey sections reflect 'buffers,' or time periods I've purposely kept clear of meetings.

"In aggregate, I schedule between 90 minutes and two hours of these buffers every day (broken down into 30- to 90-minute blocks). It's a system I developed over the last several years in response to a schedule that was becoming so jammed with back-to-back meetings that I had little time left to process what was going on around me or just think.

"... Above all else, the most important reason to schedule buffers is to just catch your breath. There is no faster way to feel as though your day is not your own, and that you are no longer in control, than scheduling meetings back to back from the minute you arrive at the office until the moment you leave. I've felt the effects of this and seen it with colleagues. Not only is it not fun to feel this way, it's not sustainable."

Virgin Group Founder Richard Branson: Treat family time as a priority over work

"When you're facing an avalanche of appointments, book time to spend with your family — put it in your work diary. You will also need to prepare your colleagues for those times when an emergency will come up at home and you'll need to drop everything to deal with it, because this is almost certain to happen.

"But rather than thinking of these two aspects of your life as antagonistic, why not combine them? As I've often said, I don’t divide work and play: It's all living."

Facebook Co-founder Dustin Moskovitz: Try no meeting Wednesdays

"One of my favorite hacks is No Meeting Wednesdays, which we borrowed from Facebook. With very few exceptions, everyone's calendar is completely clear at least one day out of the week. Whether you are Maker or a Manager (http://www.paulgraham.com/makers...), this is an invaluable tool for ensuring you have some contiguous space to do project work. For me personally, it is often the one day each week I get to code."